What are the most common symptoms of NAA15 disorder?

The most common symptoms of NAA15-related neurodevelopmental disorder include intellectual disability (~100%), speech and language delay (~97%), motor delay (~97%), autism spectrum features and behavioral issues (~91%), feeding difficulties (~57%), and mild dysmorphic features (~64%). Seizures occur in approximately 23-31% of individuals, and cardiac anomalies in about 21%.

NAA15

Clinical Presentation

Symptoms &Clinical Features

NAA15 presents with a broad spectrum of neurodevelopmental features. Recognizing these symptoms is the first step — but only genetic testing (WES, WGS, or targeted gene panels) can confirm the diagnosis.

Important: Symptoms Alone Cannot Diagnose NAA15

Many of the symptoms below overlap with other neurodevelopmental conditions. Confirming an NAA15 diagnosis requires genetic testing — including Whole Exome Sequencing (WES), Whole Genome Sequencing (WGS), or a Targeted Gene Panel. Trio-WES (child + both parents) is widely considered the gold standard. If your child presents with multiple symptoms below, speak with a clinical geneticist.

Symptom Overview

Common Features of NAA15

Percentages are drawn primarily from Cheng et al. (2018, AJHG) — the foundational cohort of 38 individuals — and broader published case series. They are approximate and may not reflect the full population. Individual presentations vary widely, and severity can differ even between individuals with the same variant.

Very Common

Intellectual Disability

~100%

Ranges from mild to severe. Affects learning, reasoning, and adaptive functioning. Severity can vary even between individuals with the same variant, including within the same family. Early intervention with educational support significantly improves outcomes.

Very Common

Speech & Language Delay

~97%

One of the most consistently reported features. Expressive language is typically more affected than receptive. Many children are late talkers; some remain minimally verbal or use AAC devices. Speech therapy is highly beneficial and early intervention matters.

Very Common

Motor Delay

~97%

Delayed gross and fine motor milestones are nearly universal. Children may be late to sit, stand, and walk. Physical and occupational therapy help build strength and coordination. Some children show meaningful catch-up with early intervention.

Common

Autism Spectrum Features / Behavioral Issues

~91%

ASD, ADHD-like behaviors, and behavioral challenges are reported in the large majority of individuals. Social communication difficulties, repetitive behaviors, and sensory sensitivities are frequently observed. Formal ASD evaluation is recommended.

Common

Hypotonia (Low Muscle Tone)

~39%

Generalized low muscle tone from infancy, affecting motor milestones and feeding. Physical and occupational therapy help build strength and coordination. Hypotonia often improves with age and intervention.

Common

Feeding Difficulties

~57%

Oral motor dysfunction, poor suck in infancy, and texture aversions. Feeding therapy and nutritional support are often required in early childhood. Reported in over half of individuals in the foundational cohort.

Common

Mild Dysmorphic Features

~64%

Mild facial dysmorphology is reported in many individuals, but there is no consistent recognizable facial pattern. Features vary widely and are generally subtle. The facial gestalt is currently nonspecific for a recognizable syndrome.

Moderate

Seizures / Epilepsy

~23–31%

Various seizure types including absence, tonic-clonic, and focal seizures. Not present in all individuals. EEG monitoring and anti-epileptic medications are standard management. Reported in approximately 23% in the foundational cohort and up to 31% in broader reviews.

Less Common

Cardiac Anomalies

~21%

Congenital cardiac defects and hypertrophic cardiomyopathy have been reported in a subset of individuals. Cardiac evaluation at diagnosis is strongly advisable. Includes structural defects and major vessel anomalies.

Less Common

Vision Problems

Reported

Strabismus (crossed eyes), refractive errors, and cortical visual impairment have been reported. A dedicated ophthalmic study found vision concerns in a meaningful subset of NAA10/NAA15 patients. Regular ophthalmology follow-up is recommended.

Spectrum

A Wide Spectrum

NAA15 is a Variable Expressivity disorder — meaning the severity and combination of symptoms differs significantly between individuals, even among those with similar genetic variants. Some individuals have mild Intellectual Disability (ID) and are largely independent; others have severe cognitive impairment and require lifelong care.

This variability makes NAA15 particularly challenging to diagnose based on clinical features alone, and underscores why genetic testing is the only reliable path to a confirmed diagnosis.

Recognize These Symptoms?

If your child has multiple symptoms listed above — especially Intellectual Disability (ID), speech delay, and Autism Spectrum Disorder (ASD) features — ask your doctor about Whole Exome Sequencing (WES).

Trio-WES (testing the child and both parents) is widely considered the gold standard. It can be ordered by a clinical geneticist or pediatric neurologist.

Learn About WES Testing Find a Geneticist

What to Do Next

Talk to Your Pediatrician

Describe the symptoms you've observed and ask for a referral to a pediatric neurologist or clinical geneticist.

Request Trio-WES

Ask specifically for Whole Exome Sequencing. Trio-WES (child + both parents) provides the most definitive results.

Connect With Our Community

While waiting for results, connect with other NAA15 families who understand exactly what you're going through.